Pokemon Sun/Moon is already a monster success as far as sales go- we knew that, owing to the fact that the game had shipped 10 million copies worldwide before it even launched. But now we know that those copies are actually selling and flying off the shelves, not just stuffing retail channels, either.
For instance, take Japan. Famitsu (via NeoGAF) reports that Pokemon Sun/Moon sold 1.9 million copies in Japan over their first three days- this makes the games one of the largest launches of all time (very few games have actually ever managed to reach this numbers this high), and no other game this year is likely to reach these numbers. Not even Final Fantasy 15.
Sales of Nintendo 3DS were also buoyed by Pokemon, ending up at 113,987 units sold, meaning the 3DS is likely to have beaten the PS4 as the highest selling platform in Japan this week again.
Admittedly, these day one numbers for Sun/Moon are actually lower than day one numbers for X/Y in 2013, which sold almost 2.1 million over their first three days- however, some of the lower numbers are probably accounted for by digital sales, which are higher for 3DS games now than they were in 2013 (and which are not tracked by Famitsu).
It’s a minor enough difference to not mar the result, which is otherwise seriously impressive. I don’t know what other game in the future will ever manage to impress in this way again, at least in Japan.